[TS-2652] Allowing cancelation of AsyncProviders. This closes #65.
[TS-2652] Allowing cancelation of AsyncProviders. This closes #65.

rahmalik/trafficserver,duke8253/trafficserver,reveller/trafficserver,clearswift/trafficserver,dyrock/trafficserver,PSUdaemon/trafficserver,PSUdaemon/trafficserver,pbchou/trafficserver,taoyunxing/trafficserver,dyrock/trafficserver,taoyunxing/trafficserver,clearswift/trafficserver,chenglongwei/trafficserver,pbchou/trafficserver,dyrock/trafficserver,rpufky/trafficserver,bryancall/trafficserver,rahmalik/trafficserver,SolidWallOfCode/trafficserver,bryancall/trafficserver,PSUdaemon/trafficserver,rahmalik/trafficserver,pbchou/trafficserver,rahmalik/trafficserver,clearswift/trafficserver,chenglongwei/trafficserver,PSUdaemon/trafficserver,bryancall/trafficserver,persiaAziz/trafficserver,clearswift/trafficserver,rpufky/trafficserver,chitianhao/trafficserver,dyrock/trafficserver,PSUdaemon/trafficserver,vmamidi/trafficserver,duke8253/trafficserver,taoyunxing/trafficserver,persiaAziz/trafficserver,vmamidi/trafficserver,reveller/trafficserver,rpufky/trafficserver,taoyunxing/trafficserver,pbchou/trafficserver,chenglongwei/trafficserver,davidbz/trafficserver,taoyunxing/trafficserver,chenglongwei/trafficserver,clearswift/trafficserver,reveller/trafficserver,taoyunxing/trafficserver,PSUdaemon/trafficserver,clearswift/trafficserver,chenglongwei/trafficserver,rpufky/trafficserver,PSUdaemon/trafficserver,bryancall/trafficserver,bryancall/trafficserver,davidbz/trafficserver,SolidWallOfCode/trafficserver,dyrock/trafficserver,chenglongwei/trafficserver,chitianhao/trafficserver,SolidWallOfCode/trafficserver,rahmalik/trafficserver,pbchou/trafficserver,duke8253/trafficserver,rpufky/trafficserver,chenglongwei/trafficserver,clearswift/trafficserver,bryancall/trafficserver,chitianhao/trafficserver,rahmalik/trafficserver,rahmalik/trafficserver,duke8253/trafficserver,vmamidi/trafficserver,rpufky/trafficserver,reveller/trafficserver,reveller/trafficserver,dyrock/trafficserver,rahmalik/trafficserver,persiaAziz/trafficserver,reveller/trafficserver,davidbz/trafficserver,taoyunxing/trafficserver,persiaAziz/trafficserver,persiaAziz/trafficserver,rpufky/trafficserver,rpufky/trafficserver,SolidWallOfCode/trafficserver,PSUdaemon/trafficserver,pbchou/trafficserver,rpufky/trafficserver,SolidWallOfCode/trafficserver,persiaAziz/trafficserver,chitianhao/trafficserver,reveller/trafficserver,taoyunxing/trafficserver,duke8253/trafficserver,duke8253/trafficserver,chitianhao/trafficserver,rahmalik/trafficserver,chitianhao/trafficserver,persiaAziz/trafficserver,chenglongwei/trafficserver,dyrock/trafficserver,vmamidi/trafficserver,duke8253/trafficserver,clearswift/trafficserver,taoyunxing/trafficserver,clearswift/trafficserver,persiaAziz/trafficserver,PSUdaemon/trafficserver,SolidWallOfCode/trafficserver,davidbz/trafficserver,chitianhao/trafficserver,davidbz/trafficserver,reveller/trafficserver,davidbz/trafficserver,vmamidi/trafficserver,vmamidi/trafficserver,SolidWallOfCode/trafficserver,reveller/trafficserver